The Effects of Protein Level and Amino Acid Balance in Wheat-Based Laying Rations

Four experiments were conducted in which laying birds were fed wheat-based diets variously supplemented with herring meal and/or amino acids. Maximum egg-mass was attained with a daily lysine intake of 0.8 to 0.85 gram per bird. Considering the daily feed consumption of birds under present practical dietary conditions, this level of intake is only possible with diets containing 0.7% to 0.75% of lysine. Birds fed diets deficient in lysine consumed more feed per day but gained less body weight and produced a smaller egg-mass than birds fed diets adequate in lysine. Under the environmental conditions of the experiments maximum production was obtained with an average daily intake of 300 to 320 Kcal. metabolizable energy of which 240–245 Kcal. were dissipated. Heat dissipation was increased when the diets were deficient in lysine.